The Cosmic Engine

             model. He proposed :.
             1) The movement of heavenly bodies could be explained by a change of reference frame.
             2) The sun is the center and the planets orbit around it.
             3) Earth travels around the Sun in one year and spins on its axis once every 24 hours .
             4) The lack of observable parallax was due to the immensity of the Universe.
             1546-1601 Tycho Brahe proposed a model which was a mixture of the Geocentric- and .
             Heliocentric model in Brahe's model :.
             1) all planets, with the exception of the Earth, orbited the sun.
             2) The sun moved around a stationary Earth.
             1571-163 Johannes Kepler First scientist to abandon orbital models based on circles and .
             Developed an accurate phenomenological model for planetary motion. Developed three.
             laws 1)planets orbit the sun in elliptical 2) the speed of the planets in their orbit .
             around the sun is roughly proportional to the distance from the Sun. . 3) the period .
             squared is proportional to the length of the orbit with each planet obeying the same .
             proportionality constant. .
             1564-1642 Galileo constructed the first telescopes and gathered evidence for the Copernican theory.
             and Kepler's third law all of these discoveries conflicted with the Ptolemaic belief.
             1642-1727 Issac Newton he was instrumental in explaining why the planets in the way they did.
             Newton was successful in linking celestial and terrestrial physics. He showed that the.
             Planets also obeyed by objects on the Earth.